Algal biofuel is basically a substitute for liquefied fossil fuels which utilizes algae. It is important to note that the algae produces oils which are rich in energy. Algal oils are alternatives to the ordinary biofuel sources, for instance, sugarcane and corn. Algae fuel similar to fossil fuel usually release carbon dioxide when they are burnt. On the other hand, algae fuel in comparison to fossil fuel releases carbon dioxide into the atmosphere which has been recently removed. Additionally, this is done through photosynthesis mostly as the algae grow. The growth of algae fuel is simple and more so advantageous (Georgianna and Mayfield, 2012, 329). Algae growth does not contaminate freshwater sources. It is less harmful to the environment and is producible using waste or saline water.
There are different chemical processes involved in the production of algal biofuels. Different organic solvents are utilized in extracting lipids. Chloroform and methanol are utilized in extracting oils from algae. The use of the chemicals is still utilized in estimating algal oils spectrophotometrically. It is easy and faster to use the chemicals, especially when handling a wide variety of samples (Georgianna and Mayfield, 2012, 329). Likewise, adding some acetic acid during the extraction process leads to extraction of more acidic phospholipids. Consequently, other chemical solvents such as butanol, isopropanol, ethanol, and hexane are essential in the production of algal biofuels.
Algal biofuels are produced using two methods namely photo-bioreactors and raceway pond method. A raceway pond is an oval loop which is about 0.5m deep. It is well aerated and has a wheel that circulates water hence preventing sedimentation. Raceway ponds are usually shallow because self-shading and optical absorption by algal cells hinder penetration of light through the algal broth (Singh, Nigam and Murphy, 2011, 329). In photo-bioreactors, a culture medium is basically contained in transparent plates. The micro-algal broth is then circulated from a reservoir. Photo-bioreactors enable algal culture environment control although they are costly compared to raceway ponds.
Algae produce both primary and secondary biofuels. Primary biofuels entail mostly naturally produced biofuels. Furthermore, the natural biofuel is produced from animal waste, landfill gas, firewood, and crop residue. Secondary biofuels are categorized into first, second and third generation biofuels (Chisti and Yan, 2011, 43). First generation biofuels include bioethanol which is produced oilseeds, corn, barley, wheat, animal fat, sugarcane, potato, beef, and sunflower. Second generation biofuels are biodiesel and bioethanol produced from wood, grass, and cassava. Moreover, third generation biofuels are usually biodiesel which is produced from microbes and microalgae.
The production of third generation biofuels is being encouraged because is it more beneficial than that of the other generations. The production of first-generation biofuels necessitates the utilization of more agricultural land leaving less land for animal and human food production. Furthermore, it also leads to environmental degradation (Singh and Olsen, 2011, 3548). In the same token, the production process of second-generation biofuels needs sophisticated and expensive technologies hence making it inappropriate for profitable commercial production. On the contrary, the advantages involved in producing third generation biofuels especially microalgae overcomes that of the other two generations (Craggs et al, 2011, 663). Microalgae have the ability to reduce greenhouse gases, produces more fats and has a faster growth rate. It grows on saline water and non-arable land. Additionally, it provides diverse renewable biofuels including biodiesel, bio-hydrogen, and methane.
Algal biofuel has a great potential to provide clean energy. Nevertheless, there exist some shortcomings which need immediate response hence necessitating that cost-benefit analysis is considered. Algae biofuel is important because it produces more energy in comparison to other sources. Algae is able to produce energy more than 30 times that produced by the second and first generation of biofuel crops (Leite, Abdelaziz and Hallenbeck, 2013, 136). Similarly, algae grow faster only requiring carbon dioxide, sunlight, and water to grow. Consequently, it is biodegradable and also has the capability to survive in wastewater.
Algae is useful when used to produce biofuel since it consumes a considerable amount of carbon dioxide. Typically, carbon dioxide is one the main causes of climate change more so when it is released into the atmosphere especially after the burning of fossil fuels (Luque, 2010, 255). According to contemporary research, using algae to produce one gallon of oil only needs approximately thirteen kilograms of carbon dioxide. Nonetheless, this is beneficial compared to first-generation biofuels. Similarly, algal biofuel production does not negatively affect global food prices and supply since the production is not necessarily done in agricultural land which is used for cultivating food crops (Stephenson et al, 2011, 616). Contrariwise, algal biofuel production has various shortcomings, for instance, it is expensive. The usage of open ponds to grow algae facilitates the possibility of contamination or viral infection. According to studies, algal biofuel production is tedious, especially during oil extraction process. Usage of artificial dryers consumes much electricity in comparison to the energy produced.
In conclusion, energy security is a major global concern hence adequate research has to be carried out to ensure environmentally-friendly and economically viable alternatives are utilized. Therefore, the only remedy which seems to meet futuristic demands is the utilization of renewable energy more so algal biofuel. Algal biofuel is a potential energy source, although there are some issues that need to be addressed. On the other hand, algae biofuel will be responsible for reducing the use of fossil fuels in the future. Subsequently, it will lessen greenhouse gases which are responsible for causing climate change.Algal oils are alternatives to the ordinary biofuel sources, for instance, sugarcane and corn. Algae fuel similar to fossil fuel usually release carbon dioxide when they are burnt. On the other hand, algae fuel in comparison to fossil fuel releases carbon dioxide into the atmosphere which has been recently removed. Algae is useful when used to produce biofuel since it consumes a considerable amount of carbon dioxide. Typically, carbon dioxide is one the main causes of climate change more so when it is released into the atmosphere especially after the burning of fossil fuels.
Chisti, Y. and Yan, J., 2011. Energy from algae: current status and future trends: algal biofuels–a status report.
Craggs, R.J., Heubeck, S., Lundquist, T.J. and Benemann, J.R., 2011. Algal biofuels from wastewater treatment high rate algal ponds. Water Science and Technology, 63(4), pp.660-665.
Georgianna, D.R. and Mayfield, S.P., 2012. Exploiting diversity and synthetic biology for the production of algal biofuels. Nature, 488(7411), p.329.
Leite, G.B., Abdelaziz, A.E. and Hallenbeck, P.C., 2013. Algal biofuels: challenges and opportunities. Bioresource technology, 145, pp.134-141.
Luque, R., 2010. Algal biofuels: the eternal promise?. Energy & Environmental Science, 3(3), pp.254-257.
Singh, A. and Olsen, S.I., 2011. A critical review of biochemical conversion, sustainability and life cycle assessment of algal biofuels. Applied Energy, 88(10), pp.3548-3555.
Singh, A., Nigam, P.S. and Murphy, J.D., 2011. Mechanism and challenges in commercialisation of algal biofuels. Bioresource technology, 102(1), pp.26-34.
Stephenson, P.G., Moore, C.M., Terry, M.J., Zubkov, M.V. and Bibby, T.S., 2011. Improving photosynthesis for algal biofuels: toward a green revolution. Trends in biotechnology, 29(12), pp.615-623.